Double salts of phenol sulfonic acids



Patented Oct. 4, 1949 UNITED STATES ATENT OFFICE DOUBLESALTS F PHENOLSULFONIC ACIDS Y John G. McNab, Cranford, and Carl'Winning,

Westfield, N. J., assignors to Standard Oil Development Company, acorporation of Delaware No Drawing. Application August 29, 1946, SerialNo. 693,812

where M and M are metals, R is hydrogen or'an alkyl group, which may bea straight or branched chain, and n is a small whole number representingthe number of alkyl groups attached to the nucleus when R is an alkylgroup. It is to be understood that in the case of polyvalent metals theremaining valences will be attached to similar groups.

If the phenol sulfonic acid salts of the present invention are tocontain alkyl groups, the acids may be prepared by reacting a phenolwith an olefin or olefin polymer in a hydrocarbon oil solution, whilegradually adding sulfuric acid under controlled temperature conditions.In this method of preparation the sulfuric acid serves both as analkylation catalyst and sulfonating agent. An alternative procedure isto first alkylate the phenol in the presence of a difierent catalyst andthen sulfonate the alkylated phenol with sulfuric acid. Thus, phenol canbe alkylated with diisobutylene (the dimer of isobutylene) in thepresence of stannic chloride and hydrogen chloride, or with a mixedbutene polymer of 16 to. 20 carbon atoms, using an A1Cl3-HC1 catalyst,when a long branched chain radical is desired. The alkyl phenol is thensulfonated as described above. The dimer, trimer, tetramer and pentamerof isobutylene are particularly desirable as alkylating agents.

Other alkylating agents which may be used are certain of the polymericmaterials obtained as lay-products in the manufacture of butyl alcoholfrom petroleum refinery butenes. These consist essentially of polymersof n-butene with small percentages of isobutene and'other olefins andmay contain an average of 16-20 or 20-24 car'- bon atoms. Low molecularweight polymers or other olefins such as ethylene, propene, pentene andisopentene or mixtures of these may also be utilized to alkylate thephenols. The terpenes may also be so used.

4 Claims. (01. 260-512) Among the more preferred starting materialsin'the preparation of the compounds of the present invention are phenol,cresol, tert.-buty1 phen01, petroleum phenols, and the like.

In order to prepare polyvalent metal double salts of the phenol sulfonicacids, it is often desirable to prepare the sodium salts first and thenconvert these to barium zinc, or other polyvalent metal salts byreaction'with a solution of an appropriate inorganic salt. For example,to

obtain a good yield of calcium double salt, the

phenol sulionic acid may be neutralized with aqueous sodium hydroxide tomake the mono sodium sulfonate, in which only the sulfonate group isneutralized, and this is then converted to the sodium double salt withalcoholic sodium hydroxide, and this salt is then treated with calciumnitrate in acetone solution to give the calcium double salt. 'It isalso'possible in the above method to convert the mono'sodium salt to thesodium double salt by dissolving it in xylene or other non-aqueoussolvent and treating it with finely divided solid sodium hydroxide, theWater of formation being removed from the reaction by suitable means.

By an alternative procedure, the phenol sulfonic acid may be neutralizeddirectly 'to the sodium double salt with alcoholic sodium hydroxide, andthis salt is then converted to the calcium double salt by treating withcalcium chloride in alcoholic solution.

'By a further method, the phenol sulfonic acid may be converted directlyto an alkaline earth metal double salt by reacting the same with analkaline earth metal'hydroxide, e. g., barium hydroxide, in the presenceof a non-aqueous solvent, such as xylene or a mineral oil, and removingthe water formed in the reaction during the process, e. g.,' byrefluxing. Other metal double salts may be similarly'formed.

By the use of the methods described above, it is possible to form doublesalts containing two different metals, one of which is attached to thesulfo group and the other substituting for hydrogen in the hydroxylgroup. H

The above described methods are particularly applicable to thepreparation of alkaline earth metal double salts of the phenol sulfonicacids but salts of other polyvalent metals may be formed in a similarmanner. 1

The following example illustrates the preparation of one of the doublesalts of the present invention, but it will be understood that thisexample is not intended to limit the scope of this invention in any way.

Preparation of calcium double salt of isohexadecyl phenol sulfonic acid296 grams of phenol, 650 grams of tetraisobutylene, and 1800 cc. oflight petroleum naphtha (boiling range of 160-240" F.) were placed in areaction vessel equipped with a stirrer and reflux condenser. 624 gramsof 96% sulfuric acid were added dropwise to this mixture and thetemperature kept below 35 C. After 8 hours of contact with the mixture,the spent acid was withdrawn and 300 grams of additional 96% sulfuricacid were contacted with the reaction mixture for another 8 hours. Thespent acid was again removed and about half of the sulfonic acid productwas neutralized with an aqueousisopropanol (30% water, 70% isopropanol)solution of sodium hydroxide. The resulting material was dried on a drumdrier, yielding 'IZO grams of a soft product. This was dissolved in 2liters of 50% isopropanol and extracted several times with lightpetroleum naphtha. The soap layer was removed and dried in a drum drier,yielding 650 grams of mono sodium isohexadecyl phenol sulfonate. Thiswas further purified by dissolving in light petroleum naphtha anddrying, yielding 459 grams of purified product.

A solution of 160 grams of the mono sodium isohexadecyl phenolsulfonate, prepared as described above, in 500 cc. of xylene was placedin a reaction vessel equipped with a stirrer and a reflux condenserattached to a water trap. 16 grams of finely divided sodium hydroxidewas added and the mixture refluxed with stirring for 2 hours, water ofreaction being removed through the trap. The reaction mixture wasevaporated to dryness at 100 C. under 3 mm. pressure. The residue wastaken up with 500 cc. of acetone, and to this was added an acetonesolution of '75 grams of calcium nitrate. The resulting precipitate wasremoved by filtration, and the filtrate was evaporated to dryness at 100C. under 3 mm. pressure. There were thus obtained 152 grams of residue,which consisted of the calcium double salt of isohexadecyl phenolsulfonic acid. It was found to contain 9.05% calcium, compared to thetheoretical value of 9.15%.

Other compounds illustrating the invention are: the calcium double saltof phenol sulfonic acid, the barium double salt oi isohexadecyl phenolsulfonic acid, the calcium double salt of xylenol sulfonic acid, thecalcium double salt of a phenol sulfonic acid in which the phenol hasbeen alkylated with a C1e-C2o polymer of essentially n-butene, the mixedbarium-zinc double salt of isoeicosyl phenol sulfonic acid, the calciumdouble salt of isododecyl phenol sulfonic acid, the tin double salt ofisododecyl cresol sulfonic acid, and the barium double salt ofdi-tert.-amyl phenol sulfonic acid. The new compounds of the presentinvention are useful as detergent additives for mineral lubricating oilswhich are to be used as crankcase lubricants for internal combustionengines.

The present invention is not to be considered as limited by any of theexamples described herein, which are given by way of illustration only.but is to be limited solely by the terms of the appended claims.

We claim:

1. The method of preparing a sodium double salt of a, phenol sulfonicacid, in which both the sulfo and hydroxyl groups are neutralized bysodium, which comprises reacting the phenol sulfonic acid with sodiumhydroxide in the presence of Water to neutralize only the sulfa group,then reacting 4 the mono sodium salt thus formed with finely dividedsodium hydroxide in the presence of a non-aqueous solvent while removingthe water of neutralization as formed.

2. The method of preparing the calcium double salt of isohexadecylphenol sulionic acid which comprises neutralizing the sulfo group ofisohexadecyl phenol sulfonic acid with an aqueous isopropanol solutionof sodium hydroxide, separating and drying the mono sodium salt thusformed, further reacting the said mono sodium salt with finely dividedsodium hydroxide in the presence of xylene while removing water ofneutralization as formed, further reacting the sodium double salt thusformed with calcium nitrate in the presence of acetone, removing theprecipitate formed, and evaporating the remaining solution to dryness.

3. The method of preparing a compound having the structure metalhydroxides in the presence of a, non-aqueous solvent While removing theWater of neutralization as formed.

4. The method of converting a compound of the structure MOaS OH where Mis a metal selected from the group consisting of alkali and alkalinemetals and R is a branched chain alkyl radical having 8 to 24 carbonatoms, into a compound of the structure REFERENCES GITED The followingreferences'are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,058,504 Rauschert Oct. 27, 19362,162,269 Mikeska June 13, 1939 2,209,169 Mikeska et a1 July 23, 1940OTHER REFERENCES Mellors Modern Inorganic Chemistry, 1939, page 620, 1page.

